1. Field of the Invention
The present invention relates to a zoom lens system, an optical apparatus equipped with the zoom lens system and a method for manufacturing the zoom lens system.
2. Related Background Art
There have been proposed zoom lens systems having a positive lens group disposed to the most object side used as an interchangeable lens for a single lens reflex camera and the like disclosed in such as a Japanese Patent Application Laid-Open No. 2008-003195. Further, over the recent years, increased strictness about ghost images and flare defined as one of factors, which affect not only aberration correction performance but also optical performance, has been requested of the zoom lens system. Therefore, a request for the higher performance is given also to an antireflection coating formed on a lens surface, and a multi-layered film design technique and a multi-layered film growth technique continue their developments (refer to, e.g., Japanese Patent Application Laid-Open No. 2000-356704).
However, the conventional zoom lens system has had a problem that when the zoom lens system is made to have a higher zoom ratio, variations in aberrations increase, so that sufficiently high optical performance has been difficult to be obtained upon zooming or upon correcting an image blur becomes large. At the same time, optical surfaces in such a zoom lens system tend to generate reflection light causing flare or ghost images.